source/programbuilder.h

   1 #ifndef MSP_GL_PROGRAMBUILDER_H_
   2 #define MSP_GL_PROGRAMBUILDER_H_
   3
   4 #include <map>
   5 #include <string>
   6 #include <vector>
   7 #include <msp/datafile/objectloader.h>
   8
   9 namespace Msp {
  10 namespace GL {
  11
  12 class Program;
  13
  14 class invalid_variable_definition: public std::invalid_argument
  15 {
  16 public:
  17         invalid_variable_definition(const std::string &w): std::invalid_argument(w) { }
  18         virtual ~invalid_variable_definition() throw() { }
  19 };
  20
  21 /**
  22 Generates shaders with common features.
  23 */
  24 class ProgramBuilder
  25 {
  26 public:
  27         /**
  28         Describes the features of a standard shader program.
  29         */
  30         struct StandardFeatures
  31         {
  32                 class Loader: public DataFile::ObjectLoader<StandardFeatures>
  33                 {
  34                 public:
  35                         Loader(StandardFeatures &);
  36                 };
  37
  38                 bool texture;
  39                 bool material;
  40                 bool lighting;
  41                 unsigned max_lights;
  42                 bool skylight;
  43                 bool specular;
  44                 bool normalmap;
  45                 bool shadow;
  46                 bool reflection;
  47                 bool legacy;
  48                 std::string custom;
  49
  50                 StandardFeatures();
  51
  52                 std::string create_flags() const;
  53         };
  54
  55 private:
  56         enum VariableScope
  57         {
  58                 NO_SCOPE,
  59                 UNIFORM,
  60                 ATTRIBUTE,
  61                 VERTEX,
  62                 FRAGMENT
  63         };
  64
  65         enum InterfaceFlags
  66         {
  67                 NO_INTERFACE = 0,
  68                 INPUT = 1,
  69                 OUTPUT = 2,
  70                 PASSTHROUGH = INPUT|OUTPUT,
  71                 GOAL = 4
  72         };
  73
  74         struct VariableDefinition
  75         {
  76                 VariableScope scope;
  77                 const char *name;
  78                 const char *type;
  79                 const char *expression;
  80                 const char *flags;
  81         };
  82
  83         struct ShaderVariable
  84         {
  85                 std::string name;
  86                 const VariableDefinition *variable;
  87                 std::string resolved_name;
  88                 bool fuzzy_space;
  89                 std::string resolved_space;
  90                 bool array_sum;
  91                 std::string array_subscript;
  92                 unsigned array_size;
  93                 std::list<ShaderVariable *> referenced_vars;
  94                 std::list<ShaderVariable *> referenced_by;
  95                 bool inlined;
  96                 bool inline_parens;
  97                 bool in_loop;
  98
  99                 ShaderVariable(const std::string &);
 100
 101                 void resolve(const VariableDefinition &);
 102                 void resolve(ShaderVariable &);
 103                 void resolve_space(const std::string &);
 104                 void resolve_array(const StandardFeatures &, unsigned = 0);
 105                 void add_reference(ShaderVariable &);
 106                 void update_reference(ShaderVariable &, ShaderVariable &);
 107                 void check_inline(bool, bool);
 108                 bool is_referenced_from(VariableScope) const;
 109                 InterfaceFlags get_interface_flags(VariableScope) const;
 110                 std::string create_declaration(char = 0, bool = false) const;
 111                 std::string create_replacement(VariableScope, const char * = 0) const;
 112                 std::string create_expression(const char * = 0) const;
 113         };
 114
 115         enum MatchType
 116         {
 117                 NO_MATCH,
 118                 EXACT,
 119                 FUZZY,
 120                 ARRAY
 121         };
 122
 123         StandardFeatures features;
 124         std::list<VariableDefinition> custom_variables;
 125         std::string feature_flags;
 126         bool optimize;
 127
 128         static const VariableDefinition standard_variables[];
 129         static const char interfaces[];
 130
 131 public:
 132         ProgramBuilder(const StandardFeatures &);
 133
 134         void set_optimize(bool);
 135         Program *create_program() const;
 136         void add_shaders(Program &) const;
 137 private:
 138         std::string create_source(const std::list<ShaderVariable *> &, VariableScope) const;
 139         bool evaluate_flags(const char *) const;
 140         static MatchType name_match(const char *, const char *, const char ** = 0);
 141         static bool parse_identifier(const char *, unsigned &, unsigned &);
 142         static std::vector<std::string> extract_identifiers(const char *);
 143         static std::string replace_identifiers(const char *, const std::map<std::string, std::string> &);
 144 };
 145
 146 } // namespace GL
 147 } // namespace Msp
 148
 149 #endif